21/19

Interval information

Ratio	21/19
Factorization	3 × 7 × 19-1
Monzo	[0 1 0 1 0 0 0 -1⟩
Size in cents	173.2679¢
Names	hendrix major second, undevicesimal submajor second, undevicesimal supraneutral second
Color name	19uz2, nuzo 2nd
FJS name	[math]\displaystyle{ \text{M2}^{7}_{19} }[/math]
Special properties	reduced
Tenney norm (log2 nd)	8.64024
Weil norm (log2 max(n, d))	8.78463
Wilson norm (sopfr(nd))	29
[sound info]
Open this interval in xen-calc

In 19-limit just intonation, 21/19 is the hendrix major second, also known as the undevicesimal submajor second or undevicesimal supraneutral second, named for falling short of the Pythagorean major second (9/8) by a hendrix comma (57/56). In counterpyth systems, it is equated to the diminished third (the interval formed by two limmas (256/243)). It can also be considered to approximate the tetracot generator.

See also

• 38/21 – its octave complement
• 19/14 – its fifth complement
• Gallery of just intervals